Machine for manufacturing tubes by helically winding a metal sheet

ABSTRACT

A machine for manufacturing tubes by helically winding a metal sheet comprises two series of rollers forming two parallely disposed outer bending members and a bearing beam having a series of rollers forming the inner bending member, said bearing beam having a horizontal shaft so that the level and pivoting of said beam are controllable for permitting the spacing and inclination of said inner bending member relative to said two outer bending members.

United States Patent [1 1 Sehaaps 1 1 MACHINE FOR MANUFACTURING TUBES BY I-IELICALLY WINDING A METAL SHEET [75] Inventor: Alhert Pierre Ghislain Sehaaps,

Embourg, Belgium [73] Assignee: Societe Anonyme des Ateliers de Construction de la Meuse. Selessin-Ougree, Belgium [22] Filed: ()et. 15, I973 [21] Appl. No.: 406,662

[521 U.S. Cl 72/l35; 72/138 [51] Int. Cl. B2ld ll/06 [581 Field of Search 72/48, 49, 135, I71) 173,

[56] References Cited UNITED STATES PATENTS Sengel .t 228/15 1451 May 13, 1975 3,407639 10/1968 Kehne 72/ 1 35 3699793 10/1972 Wagner 3,7761110 12/1973 Krakow 29/4773 Primary lz'.\'uminer-Richard .I. Herbst Attorney, Agent, or Firm-Young & Thompson 57 ABSTRACT A machine for manufacturing tubes by hclically winding a metal sheet comprises two series of rollers forming two parallely disposed outer bending members and a bearing beam having a series of rollers forming the inner bending member. said bearing beam having a horizontal shaft so that the level and pivoting of said beam are controllable for permitting the spacing and inclination of said inner bending member relative to said two outer bending members.

6 Claims, 3 Drawing Figures MACHINE FOR MANUFACTURING TUBES BY HELICALLY WINDING A METAL SHEET The present invention relates to a machine for manufacturing tubes by helically winding a metal sheet.

For the manufacture of tubes machines are already known wherein a metal sheet is forced at a given angle into a bending device which bends it and rolls it helically, whereby after welding the contiguous edges a tube is obtained whose diameter depends on the width of the metal sheet. The bending device comprises three bending members, namely two external bending members parallel to one another and supported in a horizontal plane on a support frame and one inner bending member parallel to the two outer bending members and mounted at one end of a bearing beam.

It is known to form the outer and inner bending members as three cylinders mounted with their axes parallel and extending along the edges of a triangular prism or to form them as three sets of rollers located on such axes. In what ever way they are formed the bending members are regulatable relative to one another as regards their parallelism and spacing.

In such machines in order to permit the continuous discharge of the tube being formed the inner bending member is arranged so as to overhang. Under the action of the bending force, this member has a tendency to depart from the horizontal position which it should necessarily occupy relative to the two outer members.

It may be desirable to create a counter movement, by giving this member an inclination notably with the object of opposing any difference in thickness or hardness of the sheet.

In fact it has been noted on examining a cross-section of a metal strip subjected to bending that the thickness can vary from the middle towards the two longitudinal edges and there can also be considerable differences in hardness between the centre and edges of the metal strip.

The variations in position of the inner bending member and the variations in thickness and hardness of the metal strip influence unfavourably the uniformity of bending, which causes difficulties notably during welding.

The object of the present invention is to eliminate or reduce these difficulties. Accordingly the invention provides a machine for manufacturing tubes by helically winding a metal sheet using a bending device with two parallel outer bending members carried by a frame and one inner bending member parallel thereto and disposed at one end of a bearing beam, characterised in that said bearing beam is mounted on a horizontal pivotable shaft whose level and pivoting are controllable in such a way as to permit a spacing and inclination of the inner bending member relative to the two outer parallel members.

According to one feature of the horizontal pivotal shaft is located between the two ends of the bearing beam.

According to another feature the horizontal pivotable shaft is placed at one end of the vertical rod of a hydraulic pressure jack whose supply is controlled by a variation in the level of said shaft.

According to yet another feature the bearing beam is articulated to a hydraulic jack for inclination at the end remote from the inner bending member and whereof the supply is controlled by a variation in the inclination of the bearing beam.

Other features will appear from the following description relative to the attached drawings which describe an embodiment of the invention given solely for illustration. In the drawings:

FIG. 1 is a schematic view in part side elevation of a machine showing the bearing beam of the inner bending member and the controls for the supply of the inclination and pressure jacks.

FIG. 2 is a section along the line lI-ll of FIG. 1.

FIG. 3 is a part view in front elevation on an enlarged scale of two control systems for the inclination and pressure jacks.

The bending machines to which the invention refers are well known and require neither a drawing nor a detailed description. The drawings only show those parts useful for the understanding of the invention.

The machine in question comprises a rigid elongated frame 1 at one end of which are provided two supports 2 each of which carries in known manner a set of rollers 3 forming the outer bending members. Approximately mid way along its length the frame carries stands 4 whereon are fixed four vertical columns 5 whereof the heads are joined together by means of a top 6 whereon is hung a hydraulic jack 7 whereof the rod 7a is vertical and directed downwardly. At the end 7b of said rod 7a is fixed a box comprising two horizontal plates 8a and 8b joined together by vertical members 9. Plates 8a and 8b are slidably mounted on the four columns 5. At the base of members 9 provided with counter-braces 9a are located two bearings 10 wherein rotate pivots 11a of a pivot shaft 11 introduced in two bearings 12a of a beam 12 formed by a box. At one end this beam 12 carries a set of rollers 13 forming the inner bending member which by its thrust causes the bending of sheet 35 into the form of a helix 35a.

As a result of this mounting the thrust of this bending member is modified according to the level of the pivot shaft 11 displaced by the action of jack 7. If the thrust regulated for a particular operation is modified for any reason it is automatically re-established by the device which will be described hereinafter.

To the lower plate 8a is attached one end 14a of a flexible metal tongue 14 whereof the other end is attached to a first vertical rod 15 whereon is hung a counterweight 16 (see FIG. 3). This rod which slides in guides 17 provided on a vertical support panel 18 fixed to the frame is provided with a rigid lateral arm 19 placed between two switches 20a and 20b which are fixed to a plate 21 which is vertically displaceable in two slides 18a of panel 18. Plate 21 is displaced by the manipulation of hand wheel 22 of a screw regulating system 23.

When the regulation is carried out so that the thrust of the inner bending member has a given value the pivot shaft 11 is located at a given level. If for any reason this shaft is displaced upwards tongue 14 pulls rod 15 upwards and arm 19 closes switch 20b which closes an electrical circuit (not shown) to a pump which passes oil into jack 7 behind the piston which is forced back. Rod 7a descends as do 80, 8b and 9 the two bearings 10 return the pivot shaft 11 of bearing beam 12 to the correct level.

In the opposite case i.e., if the level of shaft 11 descends then under the pull of counterweight l6 rod 15 descends and its lateral arm 19 operates switch 20a.

Thus oil is passed via a (not shown) pump into jack 7 on the sidelof the rod which moves bearings Ml upwards. Shaft ll rises and is returned to the correct level. At its end 12a remote from the inner bending member, bearing beam 12 is articulated to the end of rod 24a ofa hydraulic jack 24 mounted on the frame 1 by means of pivots 25.

A flexible metal strip 26 is attached by one end 26a to the bearing, beam 12. The other end of strip 26 is attached to a second vertical rod 27 carrying a counterweight 28. This rod 27 which slides in guides 29 on support panel 18 has a lateral arm 30 located between two switches 3111,31!) fixed to a slide block 32 sliding in slides 28a provided on plate 2ll. Slide block 32 is displaced by a screw regulation system 33 and a hand wheel 34. For a given inclination of bearing beam 12 the regulation is effected in such a way that arm 30 is located at equal distance from the push buttons of switches 31a and 31b, whilst if the inclination of beam 12 varies in one direction or the other the second rod 27 is drawn upwards'by strip 26 or downwards by counterweight 28. Arm 30 then operates one or other of the switches 3 la or 31b and by a pump not shown oil is supplied to one or other surfaces of the piston of jack 24 so that rod 24a is displaced in one or other direction thus re-establishing the previously set inclination.

The described device is advantageous because it automatically compensates accidental changes in the level of the pivot shaftof bearing beam 12 Le, changes in thrust or pressure of the inner bending member as well as variations in inclination of said beam.

What we claim is:

1. Machine for manufacturing tubes by helically winding a metal sheet, comprising a rigid frame, two parallel series of rollers disposed on said frame and forming outer bending members, vertical columns on said frame, a bearing beam suspended on said columns, a series of rollers at one end of said bearing beam forming an inner bending member parallel to said two outer bending members, a horizontal shaft supporting said beam and about the axis of which said beam pivots in termediate the ends ofthe beam, means guiding, the

I tuted by a flexible metal strip.

shaft for vertical movementon said columns afirst hydraulic pressure jack having a vertical rod forraising and lower said shaft, means for supplying'hydraulic, fluid to said first jack, means responsive to' vertical movement of said shaft in one direction to control'said supply of hydraulic fluid to said first jack to return'said shaft to a predetermined position, a second hydraulic jack articulated to the end of said beam remote from said rollers, and means responsive to variation the inclination of said beam to operate said second jack to} return said beam to a predetermined inclination.

2. Machine for manufacturing tubes according to claim ll, wherein the control of thesupply to the said j first hydraulic pressure jack comprises a first flexible ,l member attached by one end to said support meansof the horizontal shaft and by the other end to a first vertiing beam remote from the inner bending member and by the other end to a second vertical. sliding rod carry-1w 1 8 ing a second counterweight and provided with a lateral arm located between two switches for operatingisaid second jack and mounted on a slide block vertically displaceable by a screw system.

4. Machine for manufacturing tube according to. i claim 3, wherein said slide block is displaceablein guide members provided on a displaceable platefor regulating the control of said second jack.

5. Machine for manufacturing tubes according to claim 2, wherein said first flexible member is constituted by a flexible metal strip. i

6. Machine for manufacturing tubes according to I claim 3, wherein said second flexible member is cjonsti- 

1. Machine for manufacturing tubes by helically winding a metal sheet, comprising a rigid frame, two parallel series of rollers disposed on said frame and forming outer bending members, vertical columns on said frame, a bearing beam suspended on said columns, a series of rollers at one end of said bearing beam forming an inner bending member parallel to said two outer bending members, a horizontal shaft supporting said beam and about the axis of which said beam pivots intermediate the ends of the beam, means guiding the shaft for vertical movement on said columns, a first hydraulic pressure jack having a vertical rod for raising and lower said shaft, means for supplying hydraulic fluid to said first jack, means responsive to vertical movement of said shaft in one direction to control said supply of hydraulic fluid to said first jack to return said shaft to a predetermined position, a second hydraulic jack articulated to the end of said beam remote from said rollers, and means responsive to variation in the inclination of said beam to operate said second jack to return said beam to a predetermined inclination.
 2. Machine for manufacturing tubes according to claim 1, wherein the control of the supply to the said first hydraulic pressure jack comprises a first flexible member attached by one end to said support means of the horizontal shaft and by the other end to a first vertical sliding rod carrying a first counterweight and provided with a lateral arm located between two switches for operating said first pressure jack and mounted on a plate which is vertically displaceable between slides by means of a screw control for regulating said control.
 3. Machine for manufacturing tubes according to claim 1, wherein the control of the supply for said second jack for the bearing beam comprises a second flexible member attached by one end to the end of the bearing beam remote from the inner bending member and by the other end to a second vertical sliding rod carrying a second counterweight and provided with a lateral arm located between two switches for operating said second jack and mounted on a slide block vertically displaceable by a screw system.
 4. Machine for manufacturing tube according to claim 3, wherein said slide block is displaceable in guide members provided on a displaceable plate for regulating the control of said second jack.
 5. Machine for manufacturing tubes according to claim 2, wherein said first flexible member is constituted by a flexible metal strip.
 6. Machine for manufacturing tubes according to claim 3, whereIn said second flexible member is constituted by a flexible metal strip. 